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Catalyst 2975 Switch Software Configuration Guide
OL-19720-02
Chapter 20 Configuring DHCP Features and IP Source Guard Features
Configuring DHCP Server Port-Based Address Allocation
•
Preassigned addresses are automatically excluded from normal dynamic IP address assignment.
Preassigned addresses cannot be used in host pools, but there can be multiple preassigned addresses
per DHCP address pool.
•
To restrict assignments from the DHCP pool to preconfigured reservations (unreserved addresses
are not offered to the client and other clients are not served by the pool), you can enter the
reserved-only
DHCP pool configuration command.
Enabling DHCP Server Port-Based Address Allocation
Beginning in privileged EXEC mode, follow these steps to globally enable port-based address allocation
and to automatically generate a subscriber identifier on an interface.
After enabling DHCP port-based address allocation on the switch, use the
ip dhcp pool
global
configuration command to preassign IP addresses and to associate them to clients. To restrict
assignments from the DHCP pool to preconfigured reservations, you can enter the
reserved-only
DHCP
pool configuration command. Unreserved addresses that are part of the network or on pool ranges are
not offered to the client, and other clients are not served by the pool. By entering this command, users
can configure a group of switches with DHCP pools that share a common IP subnet and that ignore
requests from clients of other switches.
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
ip dhcp use subscriber-id client-id
Configure the DHCP server to globally use the
subscriber identifier as the client identifier on all
incoming DHCP messages.
Step 3
ip dhcp subscriber-id interface-name
Automatically generate a subscriber identifier based
on the short name of the interface.
A subscriber identifier configured on a specific
interface takes precedence over this command.
Step 4
interface
interface-id
Specify the interface to be configured, and enter
interface configuration mode.
Step 5
ip dhcp server use subscriber-id client-id
Configure the DHCP server to use the subscriber
identifier as the client identifier on all incoming
DHCP messages on the interface.
Step 6
end
Return to privileged EXEC mode.
Step 7
show running config
Verify your entries.
Step 8
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Содержание 2975 - Catalyst LAN Base Switch
Страница 36: ...Contents xxxvi Catalyst 2975 Switch Software Configuration Guide OL 19720 02 ...
Страница 40: ...xxxviii Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Preface ...
Страница 62: ...1 22 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 1 Overview Where to Go Next ...
Страница 398: ...13 30 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 13 Configuring VLANs Configuring VMPS ...
Страница 424: ...15 18 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 15 Configuring VTP Monitoring VTP ...
Страница 628: ...26 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 26 Configuring UDLD Displaying UDLD Status ...
Страница 660: ...28 8 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 28 Configuring RMON Displaying RMON Status ...
Страница 888: ...38 32 Catalyst 2975 Switch Software Configuration Guide OL 19720 02 Chapter 38 Troubleshooting Troubleshooting Tables ...